The invention relates to an adjustable apparatus for the quick and accurate measurement of angles and distances, and more particularly to a carpenter""s type of adjustable square that provides incrementally reproducible angular and linear measurements.
Carpentry squares have long been employed as an aid in construction and in craft. Professional carpenters, builders, wood workers, brick layers and masons are but a few trades that require a carpenters""s type of square for checking and measuring work materials. Besides professional trades persons, hobbyists and xe2x80x9cdo-it-yourselfersxe2x80x9d also use squares in a wide variety of applications in often encountered situations, each requiring the reliable and quick checking, measurement or establishment of an angle.
The standard and well known carpenter""s square is a tool that typically has either a triangular or xe2x80x9cLxe2x80x9d shape. Conventionally, two metal, wood or plastic elements or xe2x80x9clegsxe2x80x9d are joined at a right angle (90xc2x0) to form the tool. The legs of the xe2x80x9cLxe2x80x9d can be connected by a third leg to form the triangular alternative, often referred to as a xe2x80x9cspeed square.xe2x80x9d
There have been many improvements made to the carpenter""s square, often to make the square into a multi-purpose tool and to aid in the measurement of angles, other than the 90xc2x0 angle incorporated within the conventional form.
U.S. Pat. No. 5,392,525 is one such improved device, which is employed as a technical drawing tool. The drawing tool includes a circular protrusion that displays the angular relationship between two connected rulers. Though potentially useful for drawing and drafting, the angle increments are difficult to read, especially if the device is employed for actual, field carpentry work or the like, rather than on a drafting or drawing table.
U.S. Pat. No. 5,687,628 shows a guiding device for wood cutting that includes a set of guides that pivot from a common point. However, the guide lacks the ability to be set to a specific angle with precision, with out the aid of an additional angular measuring device.
U.S. Pat. No. 6,105,267 discloses an adjustable carpentry angle apparatus that includes two legs with an interconnecting link. Again, the adjustment to specific needed angles cannot be achieved without an additional angle measuring device to verify or select the desired angle between the two legs.
An adjustable apparatus is needed that can accurately reproduce angles needed in carpentry and more generally for construction. This tool must be is easily adjusted with reproducible precision, and still able to withstands the rigors of construction work.
The present invention provides an adjustable carpenter""s square for the quick and reproducible measurement of angles and distances, such as radii. The adjustable carpenter""s square includes a center bar. The center bar has a grip end and a wing end. Along the center bar, a set of indicia are inscribed. The indicia are any appropriate set of graduations upon the center bar, which may include numerical notations. A indicator slide is receivable onto the center bar. The indicator slide includes a first slide strut pivot and a second slide strut pivot.
A first strut and a second strut attach to the indicator slide. The first strut has a first wing strut end and a first slide strut end. The second strut has a second wing strut end and a second slide strut end.
A first wing attaches to the center bar and the first strut. The first wing has a first wing tip and a first center bar end. The first wing also includes a first wing strut pivot positioned between the first wing tip and the first center bar end. The first wing strut pivot hingably connects the first wing to the first strut. The first wing strut pivot attaches to the first strut proximate to the first wing strut end of the first strut.
A second wing attaches to the center bar and the second strut. Similar to the first wing, the second wing has a second wing tip and a second center bar end. The second wing includes a second wing strut pivot positioned between the second wing tip and the second center bar end. The second wing strut pivot hingably connects the second wing to the second strut. The second wing strut pivotably attaches to the second strut proximate to the second wing strut end of the second strut.
The first wing pivotably connects to the center bar at a first wing hinge. The first wing hinge is proximate to the first center bar end of the first wing, and the first wing hinge is proximate to the wing end of the center bar.
The second wing pivotably connects to the center bar at a second wing hinge. The second wing hinge is proximate to the second center bar end of the second wing, and the second wing hinge proximate to the wing end of the center bar.
The indicator slide includes a first slide strut pivot and a second slide strut pivot. The first slide strut pivot on the indicator slide connects to the first strut proximate to the first slide strut end of the first strut. The second slide strut pivot on the indicator slide connected to the second strut proximate to the second slide strut end of the second strut.
A measured relation is formed between the first wing with the second wing. The position of the indicator slide on the center bar is relatable to the measured relation by way of the set of indicia displayed on the center bar. The indicator slide directly corresponds to the measured relation, formed between the first wing and the second wing. Additionally, the indicator slide can be employed to select the measured relation desired. The measured relation can include such values as: angles, pitches, radii, diameters, distances, segments, arcs and chords.
In a preferred alternative of the present invention, the user can lock the indicator slide in any position along the center bar. The locked-in measured relation can then be translated and reproduced, as desired.